lkml.org 
[lkml]   [2013]   [Sep]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    SubjectRe: ????: [PATCH 34/50] sched: numa: Do not trap hinting faults for shared libraries
    On Tue, Sep 17, 2013 at 10:02:22AM +0800, ?????? wrote:
    > index fd724bc..5d244d0 100644
    > --- a/kernel/sched/fair.c
    > +++ b/kernel/sched/fair.c
    > @@ -1227,6 +1227,16 @@ void task_numa_work(struct callback_head *work)
    > if (!vma_migratable(vma))
    > continue;
    >
    > + /*
    > + * Shared library pages mapped by multiple processes are not
    > + * migrated as it is expected they are cache replicated. Avoid
    > + * hinting faults in read-only file-backed mappings or the vdso
    > + * as migrating the pages will be of marginal benefit.
    > + */
    > + if (!vma->vm_mm ||
    > + (vma->vm_file && (vma->vm_flags & (VM_READ|VM_WRITE)) == (VM_READ)))
    > + continue;
    > +
    >
    > =?? May I ask a question, we should consider some VMAs canot be scaned for BalanceNuma?
    > (VM_DONTEXPAND | VM_RESERVED | VM_INSERTPAGE |
    > VM_NONLINEAR | VM_MIXEDMAP | VM_SAO));

    vma_migratable check covers most of the other VMAs we do not care
    about. I do not see the point of checking for some of the VMA flags you
    mention. Please state which of the additional flags that you think should
    be checked and why.

    --
    Mel Gorman
    SUSE Labs


    \
     
     \ /
      Last update: 2013-09-17 10:21    [W:4.140 / U:0.560 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site